According to the Principle of Sufficient Reason (henceforth ‘PSR’), everything has an explanation or sufficient reason. This paper addresses three questions. First, how continuous is the contemporary notion of grounding with the notion of sufficient reason endorsed by Spinoza, Leibniz, and other rationalists? In particular, does a PSR formulated in terms of ground retain the intuitive pull and power of the PSR endorsed by the rationalists? Second, to what extent can the PSR avoid (...) the formidable traditional objections levelled against it if it is formulated in terms of ground? And finally, how might historical discussion of the PSR shed light on the contemporary notion of grounding? (shrink)

The Principle of Sufficient Reason (PSR) holds that, for everything that exists or occurs or holds true, there is a reason why that is the case. I consider three possible ways of relating physics to the PSR: past states as reasons for present states, reasons why the laws of physics take the form that they do, and reasons why there is anything at all. In each case I suggest that the PSR is not the best way (...) of thinking about how and why physics works. -/- Invited reflection for The Principle of Sufficient Reason (Oxford Philosophical Concepts), Eds. F. Amijee and M. Della Rocca (forthcoming 2024). (shrink)

The Principle of Sufficient Reason says that all contingent facts must have explanation. In this 2006 volume, which was the first on the topic in the English language in nearly half a century, Alexander Pruss examines the substantive philosophical issues raised by the Principle Reason. Discussing various forms of the PSR and selected historical episodes, from Parmenides, Leibnez, and Hume, Pruss defends the claim that every true contingent proposition must have an explanation against major objections, (...) including Hume's imaginability argument and Peter van Inwagen's argument that the PSR entails modal fatalism. Pruss also provides a number of positive arguments for the PSR, based on considerations as different as the metaphysics of existence, counterfactuals and modality, negative explanations, and the everyday applicability of the PSR. Moreover, Pruss shows how the PSR would advance the discussion in a number of disparate fields, including meta-ethics and the philosophy of mathematics. (shrink)

The Principle of Sufficient Reason is very seldom, if ever, referred to in the works of whom we might think of as the eminent Asian metaphysicians. In spite of this, the big picture metaphysical views available in the thought of philosophers such as Nāgārjuna, Fazang and Nishida appear to share certain structural features with views more familiar to us from our own tradition; views that explicitly accept or reject the Principle of Sufficient Reason. Nāgārjuna (...) looks to develop a kind of metaphysical infinitism, Fazang an extreme form of coherentism, and Nishida a species of foundationalism. These three positions - infinitism, coherentism and foundationalism - are typically thought to exhaust the spread of possibilities by those working within the Western tradition. -/- In spite of their similarities to positions advanced within our own tradition, the cosmologies of many of the giants of Asian philosophy are characterised by their rather striking conclusions. Amongst such conclusions for Nāgārjuna is that everything is empty; for Fazang that everything is identical to everything else; and for Nishida that everything depends on absolute nothingness. If the Principle of Sufficient Reason is playing a role in the derivation of such striking conclusions, then it looks that there are more options regarding the metaphysical structure of the world available to us than our own tradition typically courts. If, on the other hand, these striking cosmological conclusions are arrived at without any consideration of sufficient reason, then there may well be ways of reasoning about the overarching structure of reality that are powerful but unfamiliar to Western thinking. In this contribution, I explore what, if any, role the PSR might be playing in the thought of Nāgārjuna , Fazang and Nishida, and what we might be able to learn from it. (shrink)

The Principle of Sufficient Reason —the principle that everything has a reason—plays a central role in Leibniz’s philosophical system. It is rather difficult, however, to determine what Leibniz’s attitude towards the modal status of the PSR is. The prevailing view is that Leibniz takes the PSR to be true necessarily. This paper develops a novel interpretation and argues that Leibniz’s PSR is a contingent principle. It also discusses whether a merely contingent PSR can do (...) the metaphysical heavy lifting that Leibniz aims for. The paper shows that, despite appearance to the contrary, this is possible. In a nutshell, the argument is that the only possible PSR violation Leibniz allows for is God’s creation of a suboptimal world; there is no Leibnizian possible world, though, which intrinsically violates the PSR. Despite its contingency, then, Leibniz’s PSR is modally robust enough to serve as a foundational principle of his metaphysics. (shrink)

Alexander Pruss’s Principle of Sufficient Reason states that every contingent true proposition has an explanation. Pruss thinks that he can plausibly maintain both his PSR and his account of libertarian free will. This is because his libertarianism has it that contingent true propositions reporting free choices are self-explanatory. But I don’t think Pruss can plausibly maintain both his PSR and libertarianism without a rift occurring in one or the other. Similar to the old luck/randomness objection, I contend (...) that Pruss’s libertarianism is susceptible to what I call “the inexplicability objection”, which attempts to show that agents’ free choices involve contingent brute facts. Pruss may be able to partially explain a proposition such that Jones freely chose A for reason R, but he cannot adequately explain a contrastive proposition such as that Jones freely chose A for R rather than B for R*. The result is that either PSR is too explanatorily permissive for libertarianism, or libertarianism is too explanatorily impermissive to satisfy PSR. After considering what I take to be Pruss’s best response to the inexplicability objection, I conclude that his attempt to reconcile PSR and libertarianism is unsuccessful. (shrink)

Peter van Inwagen presented a powerful argument against the Principle of Sufficient Reason, which I henceforth abbreviate as ‘PSR’. For decades, the consensus was that this argument successfully refuted PSR. However, now a growing consensus holds that van Inwagen’s argument is fatally flawed, at least when ‘sufficient reason’ is understood in terms of ground, for on this understanding, an ineliminable premiss of van Inwagen’s argument is demonstrably false and cannot be repaired. I will argue that (...) this growing consensus is mistaken and that a powerful argument relevantly similar to van Inwagen’s should still concern us, even when we understand ‘sufficient reason’ in terms of ground. (shrink)

Leibniz, and many following him, saw the Principle of Sufficient Reason (PSR) as pivotal to a scientific (demonstrated) metaphysics. Against this backdrop, Kant is expected to pay close attention to PSR in his reflections on the possibility of metaphysics, which is his chief concern in the Critique of Pure Reason. It is far from clear, however, what has become of PSR in the Critique. On one reading, Kant has simply turned it into the causal principle (...) of the Second Analogy. On a different reading, PSR is but the supreme principle of reason, which roughly states that, if the conditioned is given, so is the unconditioned. On my reading, PSR appears in the guises of both the causal principle and the supreme principle. This twofold specification, I argue, is key to understanding (i) Kant’s allegations that past metaphysicians failed to prove PSR, (ii) his own Critical account of the possibility of metaphysics in both of its parts (ontology and metaphysics proper), and (iii) his nuanced answer to the contentious question about the relation between physical inquiry and metaphysical reasoning about nature (both being quests for reasons). (shrink)

According to Principles of Sufficient Reason, every truth (in some relevant group) has an explanation. One of the most popular defenses of Principles of Sufficient Reason has been the presupposition of reason defense, which takes endorsement of the defended PSR to play a crucial role in our theory selection. According to recent presentations of this defense, our method of theory selection often depends on the assumption that, if a given proposition is true, then it has (...) an explanation, and this will only be justified if we think this holds for all propositions in the relevant group. I argue that this argument fails even when restricted to contingent propositions, and even if we grant that there is no non-arbitrary way to divide true propositions that have explanations from those that lack them. Further, we can give an alternate explanation of what justifies our selecting theories on the basis of explanatory features: the crucial role is not played by an endorsement of a PSR, but rather by our belief that, prima facie, we should prefer theories that exemplify explanatory power to greater degrees than their rivals. This guides our theory selection in a manner similar to ontological parsimony and theoretical simplicity. Unlike a PSR, our belief about explanatory power gives us a prima facie guiding principle, which provides justification in the cases where we think we have it, and not in the cases where we think we don't. (shrink)

The term “principle of sufficient reason” (PSR) was coined by Leibniz, and he is often regarded as its paradigmatic proponent. But as Leibniz himself often insisted, he was by no means the first philosopher to appeal to the idea that everything must have a reason. Histories of the principle attribute versions of it to various ancient authors. A few of these studies include—or at least do not exclude—medieval philosophers; one finds the PSR in Abelard, another (...) finds it in Aquinas. And while Leibniz retains pride of place in these histories, Spinoza is sometimes said to precede him “in appreciating the importance of the Principle and placing it at the center of his philosophical system.” In this paper, the author argues that the same should be said of the Islamic philosopher Avicenna. Writing 600 years before his early modern counterparts, Avicenna routinely and consistently appeals to the PSR in generating his metaphysical system. The paper aims first to establish that Avicenna deserves a position of prominence in histories of the PSR, and then to consider how he addresses certain challenges to the PSR, especially the threat posed by necessitarianism. (shrink)

Kant's attack on metaphysics consists in large part in his attack on a principle that he names the Supreme Principle of Pure Reason. This principle, it is not often noticed, is the Principle of Sufficient Reason [PSR]. In interpreting this principle as such, I argue that Kant's attack on the PSR depends on Kant's claim that existence is not a first-order predicate. If existence isn't what Kant calls a real predicate, the PSR (...) is false. While this constitutes a powerful Kantian argument against dogmatic rationalism, it also poses a problem for Kant. For, as I argue, if the PSR is true, Kant's argument that existence isn't a first-order predicate is false. In this sense, Kant's attack on the PSR is begging the question vis-á-vis radical metaphysicians. Concluding the paper I suggest relying on Kant's 'is'/'ought' distinction in avoiding this circularity, thereby reinforcing the Kantian critique. (shrink)

The Clarke/Rowe version of the Cosmological Argument is sound only if the Principle of Sufficient Reason (PSR) is true, but many philosophers, including Rowe, think that there is not adequate evidence for the principle of sufficient reason. I argue that there may be indirect evidence for PSR on the grounds that if we do not accept it, we lose our best justification for an important principle of metaethics, namely, the Principle of Universalizability. (...) To show this, I argue that all the other justifications of the Principle of Universalizability on offer, including Richard Hare's, are inadequate. (shrink)

This essay examines arguments offered in support of the Principle of Sufficient Reason (PSR) by Leibniz and his followers as well as Hume's critique of the PSR. It is shown that Leibniz has a defensible argument for the PSR, whereas the arguments of his self-proclaimed followers are weak. Thus, Hume's challenge is met by Leibniz, by Wolff and Baumgarten not so much.

The Principle of Sufficient Reason must be justified dialectically: by showing the disastrous consequences of denying it. We formulate a version of the Principle that is restricted to basic natural facts, which entails the obtaining of at least one supernatural fact. Denying this principle results in extreme empirical skepticism. We consider six current theories of empirical knowledge, showing that on each account we cannot know that we have empirical knowledge unless we all have a priori (...) knowledge of the PSR. We consider objections based on Neo-Humeanism and the essentiality of origins, and we consider the possibility that we have empirical knowledge without knowing it. (shrink)

Leibniz often refers to the Principle of Sufficient Reason (PSR) as something like a first principle. In some texts, however, he attempts to give positive arguments in its favor. I examine two such arguments, and find them wanting. The first argument has two defects. First, it is question-begging; and second, when the question-begging step is excised, the principle one can in fact derive is highly counter-intuitive. The second argument is valid, but has the defect of (...) only reaching a nearly trivial conclusion. (shrink)

The Clarke/Rowe version of the Cosmological Argument is sound only if the Principle of Sufficient Reason is true, but many philosophers, including Rowe, think that there is not adequate evidence for the principle of sufficient reason. I argue that there may be indirect evidence for PSR on the grounds that if we do not accept it, we lose our best justification for an important principle of metaethics, namely, the Principle of Universalizability. To (...) show this, I argue that all the other justifications of the Principle of Universalizability on offer, including Richard Hare's, are inadequate. (shrink)

I show how the Cosmological Argument (CA) is undermined by one of its own premises: the Principle of Sufficient Reason (PSR). First, I explain the type of CA that I am thinking about. Second, I explain a traditional modal objection against the PSR, which is ultimately based upon our intuitions in favor of contingency. Third, I show how this modal objection begs the question against the necessitarian, and then I reformulate the CA in more neutral terms. Fourth, (...) using this more neutral version of the CA, I argue that the main problem with the PSR goes way beyond its apparent necessitarian consequences. As an argument used by Bradley shows, embracing the rationalist path that underlies the PSR seems to commit us to a form of Radical Monism. I conclude by showing how this result ultimately undermines the CA. (shrink)

According to the unrestricted version of the Principle of Sufficient Reason (PSR), every truth has an explanation. I argue that there is defeasible methodological justification for belief in an unrestricted PSR. The argument is based on considerations about our cognitive limitations. It is possible that our cognitive limitations prevent us from even recognizing the explanatorily open character of some propositions we can now represent: the fact that these propositions are explicable in the first place. If this is (...) the case, then a proper recognition of our limitations and a standing goal of reasoning to attain complete explanatory knowledge justify the adoption of an unrestricted PSR. (shrink)

There is a ubiquitous claim in the grounding literature that metaphysical foundationalism violates the principle of sufficient reason (PSR) in virtue of positing a level of ungrounded facts. I argue that foundationalists can accept the PSR if they are willing to replace funda- mentality as independence with completeness and deny that ground is a strict partial order. The upshot is that the PSR can be compatible with both metaphysical foundation- alism and metaphysical infinitism, and so presupposing this (...) fixed explanatory demand need not beg the question in favour of either view. (shrink)

The aim of this paper is to defend the ontological Principle of Sufficient Reason (PSR-O). I analyse various versions of this principle and various ways of justifying it. Then I attempt to challenge some counterexamples allegedly refuting a universal application of the PSR-O. There are standard and non-standard versions of the PSR-O. The PSR-Ostand can only be valid if there are no chains of contingent reasons and outcomes with first modules, i.e. all chains are actually infinite. (...) However, there are serious arguments against this possibility. The necessary condition of the PSR-Onon-stand is the existence of a necessary substance: that substance would be a direct reason of certain contingent states of affairs obtaining in its domain, and those states of affairs would then be indirect reasons for all other contingent states of affairs and things. There are two advantages of the PSR-Onon-stand: a nomological unity of the world and explanatory simplicity. (shrink)

Outlines a conceptual argument against the Principle of Sufficient reason. The argument is presented in detail in earlier work, and is based on deductive inferences from PSR's own concept of explanation. The argument shows that not everything can have an explanation of the sort claimed by PSR. So far from being a presupposition of reason itself, as some think, PSR can be refuted by reason, arguing only from PSR's own concept of explanation. Hence PSR cannot (...) be used to argue that there must be some explanation or reason for existence, invisible at least to science, or that because we do not or cannot know the explanation, there must be irreducible mystery about why there is anything at all rather than nothing, including why there was a Big Bang in the first place. (shrink)

The early modern period was the natural historical habitat of the Principle of Sufficient Reason, i.e., the demand that everything must have a cause, or reason. It is in this period that the principle was explicitly articulated and named, and throughout the period we find numerous formulations and variants of the PSR and its closely related ‘ex nihilo nihil fit’ principle, which the early moderns inherited from medieval philosophy. Contemporary discussions of these principles were (...) not restricted to philosophy. “Nothing will come of nothing; speak again” old King Lear tells his daughter Cordelia at the beginning of Shakespeare’s celebrated tragedy, and in early modern science, conservation principles were the order of the day. Within philosophy, Malebranche stipulates that there cannot be an effect without a cause, and Berkeley motivates his idealism by an appeal to ‘ex nihilo nihil fit.’ Were we to try to provide an exhaustive survey the various formulations of the PSR in this period – including the weaker ones – we would be writing an encyclopedia. In fact, one wonders whether any early modern thinker was willing to accept a wholesale rejection of the PSR, i.e., a view which states that no fact requires an explanation. Moreover, the view that many – perhaps most – facts require an explanation seems to be tacitly assumed even by us today, in both our theoretical and colloquial discourse. For these reasons, this chapter will focus on two early modern philosophers who advocated very strong (i.e., virtually exceptionless) versions of the PSR: Benedict de Spinoza and G.W. Leibniz. Following a brief overview of Descartes’s restricted endorsement of the PSR, I will turn to discuss the central features of the PSR in the writings of Spinoza (§2) and those of Leibniz (§3). In the cases of each of these philosophers, we will examine carefully: (i) their main statements of the PSR, (ii) the scope they assign to the principle (i.e., what requires an explanation and what counts as an explanation), (iii) the modal strength they assign to the principle, (iv) the main implications they draw from the principle, (v) exceptions to the principle, and, finally, (vi) the justification of the principle. In §4, we will study a principle, complementing the PSR, namely, the assertion that everything and every fact must have an effect (or as Leibniz would put it: “nothing is sterile”). (shrink)

This paper defends the Principle of Sufficient Reason, taking Baumgarten as its guide. The primary aim is not to vindicate the principle, but rather to explore the kinds of resources Baumgarten originally thought sufficient to justify the PSR against its early opponents. The paper also considers Baumgarten’s possible responses to Kant’s pre-Critical objections to the proof of the PSR. The paper finds that Baumgarten possesses reasonable responses to all these objections. While the paper notes that (...) in the absence of a response to Kant’s Critical discussion of the PSR, this result does not vindicate the principle, it shows how this discussion provides a deeper understanding of what, according to Baumgarten, the PSR really assumes and intends, and prepares the way for a more responsible discussion of Kant’s critical objections to Baumgarten’s supposed proof. (shrink)

Canonical defenders of the principle of sufficient reason (PSR), such as Leibniz and Spinoza, are metaphysical foundationalists of one stripe or another. This is curious since the PSR—which says that everything has a ground, cause, or explanation—in effect, denies fundamental entities. In this paper, I explore the apparent inconsistency between metaphysical foundationalism and approaches to metaphysical system building that are driven by a commitment to the PSR. I do so by analyzing how Indian Buddhist philosophers arrive at (...) foundationalist and anti-foundationalist positions motivated by implicit commitments to different versions of the PSR. I begin by introducing the Buddhist principle of dependent origination (pratītyasamutpāda) as a proto-PSR that is restricted to causal explanation. Next, I show how Vasubandhu’s Sautrāntika Abhidharma metaphysics is shaped by a qualified commitment to both causal and metaphysical grounding versions of the PSR. I then reveal how Nāgārjuna’s Madhyamaka metaphysics is driven by an unrestricted and exceptionless commitment to causal and metaphysical grounding versions of the PSR. Finally, I consider how Nāgārjuna’s account may put him in a unique position to respond to a common contemporary objection to the PSR from necessitarianism. I conclude by addressing a competing interpretation on which Nāgārjuna is best understood as an anti-rationalist rather than an uber-rationalist, as I characterize him. (shrink)

Leibniz's principle of sufficient reason is the claim that everything has a sufficient reason. But is Leibniz committed to the necessity or to the contingency of his great principle? I argue that Leibniz is committed to its contingency, given that he allows for the absolute possibility of entities that he claims violate the PSR. These are all cases of qualitatively indiscernible entities, such as indiscernible atoms, vacua, and bodies. However, Leibniz's commitment to the contingency (...) of the PSR seems to stand in tension with his inference of the PSR from his theory of truth. I argue that this apparent tension can be resolved satisfactorily. When it comes to his modal views on the PSR, Leibniz's position is entirely consistent. (shrink)

For Kant one of the goals of any critique of pure reason is to answer the question, how are a priori synthetic propositions possible? Because rationalists such as Eberhard and Wolff took the principle of sufficient reason (hereafter, the PSR) as the principle of all a priori synthetic judgments, understanding both the various formulations of this principle and arguments in favor of its use as an axiom in metaphysical reasoning provides an interesting back door (...) to understanding The Critique of Pure Reason. Despite his statements in the First Critique rejecting the PSR as a principle of judgment1, I argue that Kant was actually more sympathetic to the PSR than these passages alone would suggest. The Kant-Eberhard Controversy suggests that, even though Kant explicitly denies that the PSR can guide metaphysical reasoning, he actually presupposes its truth. I show that Kant’s position is tenable because, like the rationalists, Kant accepts the assumption that real essences exist and that they ground real possibility2; this leads him to accept the truth of all clear statements of the PSR. Unlike the rationalists, however, he does not accept the assumption that human understanding is isomorphic with real essences. As a result, Kant rejects only the use of the PSR to determine a priori the existence or properties of a thing. In this paper I hope to illuminate this position. I will begin with a survey of the various formulations of the PSR that have been put forward by Kant and his predecessors: Leibniz, Eberhard, and Wolff. Then I will examine Wolff and Eberhard’s arguments in favor of the PSR along with Kant’s criticisms of these arguments. Lastly, I will show why Kant rejected the very possibility of justifying this use of the PSR while presupposing its truth. (shrink)

Shamik Dasgupta (2016) proposes to tame the Principle of Sufficient Reason (PSR) to apply to only non-autonomous facts, which are facts that are apt for explanation. Call this strategy to tame the PSR the taming strategy. In a recent paper, Della Rocca (2020a) argues that proponents of the taming strategy, in attempting to formulate a restricted version of the PSR, nevertheless find themselves committed to endorsing a form of radical monism, which, in turn, leads right back to (...) an untamed-PSR. Suppose, for the sake of argument, that Della Rocca is right. My question is this: Is there reason to believe the principle of sufficient reason (in its untamed version)? In this paper, I argue that it is impossible for there to be a reason to believe the untamed-PSR. (shrink)

The aim of this paper is to render a detailed analysis of the correspondence with Clarke in order to shed some light in the relationship between the Principle of Identity of Indiscernibles and the Principle of Sufficient Reason. Most of the secondary literature takes for granted that Leibniz derives the Principle of Identity of Indiscernible from the Principle of Sufficient Reason in at least some parts of the correspondence. This would render the (...) Principle of Identity of Indiscernibles a merely contingent truth and not a necessary principle. I will argue that this interpretation is misleading, and that Leibniz never abandoned the idea that the Principle of Identity of Indiscernibles is a necessary truth. Although he is continuously using the Principle of Sufficient Reason in his argumentation, he keeps in parallel a strong argumentation that entails the necessity of the Principle of Identity of Indiscernibles. To achieve this goal, it will be necessary to point out first some contextual facts that may determine a correct understanding of the correspondence. It will be also necessary to frame the discussion about the principles into the broader debate on the possibility of Newtonian space. Finally, it will be shown that the mentioned hypothesis is supported by textual evidence throughout the entire correspondence. (shrink)

I examine several alleged grounds of the principle of sufficient reason in Leibniz’s philosophy. These include the nature of a requisite and a sufficient condition, the nature of truth, and the nature of harmony. I argue that Leibniz does not ground the PSR in any of these ways. Instead, he is committed to a value-based grounds of the PSR: God creates the best possible world, and the fact that the PSR obtains in this world contributes to (...) it being the best. I conclude by considering some objections to this way of grounding the PSR. (shrink)

The relation between leibniz's logical and his metaphysical views is the subject of much modern scholarship. Some commentators have argued that his metaphysics is based on his logic; others have taken the opposite position. However, Both sides pose the question in terms of 'priority'. On the contrary, I argue that it is likely that leibniz means the psr to play "both" a logical and a metaphysical role. The ambiguity of leibniz's psr indicates that he equates the metaphysical notion of causation (...) with the logical notion of deduction. The psr's ambiguity results less from any confusion on leibniz's part between the notions of cause and reason, Than from his desire to identify logic and metaphysics. That identity is achieved not by reducing one to the other, But by incorporating them on an equal basis into a single discipline. (shrink)

It can be shown by means of a paradox that, given the Principle of Sufficient Reason, there is no conjunction of all contingent truths. The question is, or ought to be, how to interpret that result: _Quid sibi velit?_ A celebrated argument against PSR due to Peter van Inwagen and Jonathan Bennett in effect interprets the result to mean that PSR entails that there are no contingent truths. But reflection on parallels in philosophy of mathematics shows it (...) can equally be interpreted either as a proof that there are "too many" contingent truths to combine in a single conjunction or as a proof that the concept _contingent truth_ is indefinitely extensible and there is no such thing as "all contingent truths." Either interpretation would reconcile PSR with contingent truth, but the natural rationales of those interpretations are at odds. This essay argues that the second interpretation is a more satisfactory explanation of why, if PSR is true, there should be no conjunction of all contingent truths. This sheds new light on the nature of the explanatory demand embedded in PSR and uncovers a number of surprising implications for the commitments of rationalism. (shrink)

It is argued first, that Spinoza's Principle of Sufficient Reason (PSR) is best seen as an auxiliary premise and not as an axiom of the Ethics; second, that Spinoza held the PSR to be a self-evident truth that indicates a necessary condition for clearly and distinctly representing the existence or non-existence of a thing; and third, that this interpretation of Spinoza's PSR explains the near absence of the PSR within the demonstrations of the Ethics as well as (...) the importance of the principle in Spinoza's thought. (shrink)

This article defends the principle of sufficient reason (PSR) from a simple and direct valid argument according to which PSR implies that there is a truth that explains every truth, namely an omni-explainer. Many proponents of PSR may be willing to bite the bullet and maintain that, if PSR is true, then there is an omni-explainer. I object to this strategy by defending the principle that explanation is irreflexive. Then I argue that proponents of PSR can (...) resist the conclusion that there is an omni-explainer by denying that explanation distributes over conjunction. In the final section, I consider a plausible revision of this assumption. I argue there that, given the revised assumption, PSR seems to yield a striking picture of the explanatory structure of the universe. I explain why the resulting model does not appear utterly implausible to me. (shrink)

According to the Principle of Sufficient Reason (‘PSR’), every fact has an explanation for why it obtains. If the PSR is true, there must be a sufficient reason for why God chose to create our world. But a sufficient reason for God’s choice plausibly necessitates that choice. It thus seems that God could not have done otherwise, and that our world exists necessarily. We therefore appear forced to pick between the PSR, and the (...) contingency of creation and divine choice. I show that a third option remains open, and thus that it is possible to preserve the contingency of creation and divine choice even while endorsing the PSR. My solution depends on the coherence of a restricted modal realism. On this modal realism, there is more than one possible morally optimal created world, and for each such world there is an existing possibility in which God creates that world. (shrink)

Descartes famously espouses modal voluntarism, the doctrine that God freely creates the eternal truths. God has chosen to make it true that two plus two equals four, for instance, but he could have chosen otherwise. Why, though, does Descartes endorse modal voluntarism? Many commentators have noted that he regularly appeals to divine omnipotence to justify his doctrine. This strategy is usually thought to be unsuccessful, however, because it seems to presuppose—question-beggingly—that the eternal truths are in the scope of God’s power. (...) This paper argues that Descartes’s appeal to divine omnipotence has more going for it than meets the eye. Like many other medieval and early modern philosophers, Descartes assumes that God has the power to control everything that remains unfixed by his own essence. At the same time, though, he denies that the eternal truths are fixed by, or grounded in, the divine essence. The combination of these two commitments leads to modal voluntarism. The paper also argues that the Principle of Sufficient Reason (PSR) may play an important role in the reasoning that leads Descartes to endorse modal voluntarism. This is surprising, given that the PSR appears to be deeply at odds with modal voluntarism. (shrink)

The main thesis of Michael Della Rocca’s outstanding Spinoza book (Della Rocca 2008a) is that at the very center of Spinoza’s philosophy stands the Principle of Sufficient Reason (PSR): the stipulation that everything must be explainable or, in other words, the rejection of any brute facts. Della Rocca rightly ascribes to Spinoza a strong version of the PSR. It is not only that the actual existence and features of all things must be explicable, but even the inexistence (...) – as well as the absence of any feature of any thing – demands an explanation. Della Rocca does not stop here, however. He feeds his PSR monster with some more powerful steroids and suggests that Spinoza advocates what he terms “the twofold use of the PSR.” It is not only that everything must be explained and made intelligible, but it must ultimately be explained in terms of explainability or intelligibility itself. This twofold use of the PSR is the key to the entire book. Della Roca’s strategy throughout the book is to argue that any key feature of Spinoza’s system – be it causality, inherence, essence, consciousness, existence, rejection of teleology, goodness or political right – must be explained, and ultimately it must be explained in terms of intelligibility. “Spinoza single-mindedly digs and digs until we find that the phenomenon in question is nothing but some form of intelligibility itself, of explicability itself” (Della Rocca 2008a: 2). Della Rocca’s book came out together with a cluster of articles in which he develops in detail his new reading of Spinoza. In one of these articles, he warns the reader: “Don’t let me start” (Dell Rocca 2010: 1). The train that is about to embark leads to very bizarre terrain, and thus one should think twice before embarking on the “PSR Express.” In this paper I argue that the train was hijacked. This was a perfect crime: without anyone noticing it, the engine driver diverted the train to a new route, and as with other perfect crimes, it is none but the criminal himself who is capable of, and indeed will, bring about his own demise. As I will later argue, Della Rocca’s “PSR-on-steroids” will eventually cripple reason itself. But let us not run too fast, and start at the very beginning. I happily – or at least, so I think - board the “PSR Express.” I believe Spinoza is strongly committed to the PSR and makes very significant use of this principle, but, unlike Della Rocca, I do not think the PSR is the key to all mysteries Spinozist, nor do I believe Spinoza was committed to the reductionist program of explaining all things through intelligibility (i.e., the second use of the PSR). (shrink)

In one of its versions, the principle of sufficient reason maintains that every true proposition has a sufficient reason for its truth. Recently, a number of philosophers have argued against the principle on the ground that there are propositions such as the conjunction of all truths that are ‘too big’ to have a sufficient reason. The task of this article is to show that such maximal propositions pose no threat to the (...) class='Hi'>principle. According to what is perhaps the most ‘popular’ version of the principle to sufficient reason (PSR), every true proposition has a sufficient reason why it is true. Peter van Inwagen formulates the principle as follows: ‘for every truth, for everything that is so, there is a sufficient reason for its being true or being so.’ Like many contemporary philosophers, however, he rejects the principle. My purpose here is to show that the main philosophical argument against PSR rests on a mistaken assumption. There is also a ‘scientific’ argument against PSR that turns on considerations of quantum indeterminacy; but that argument lies beyond the scope of this discussion. (shrink)

This paper presents an argument for the Principle of Sufficient Reason, the PSR, the principle according to which each thing that exists has an explanation. I begin with several widespread and extremely plausible arguments that I call explicability arguments in which a certain situation is rejected precisely because it would be arbitrary. Building on these plausible cases, I construct a series of explicability arguments that culminates in an explicability argument concerning existence itself. This argument amounts to (...) the claim that the PSR is true. The plausibility of the initial cases in the series provides the basis of an argument for the PSR, an argument that can be rebutted only by drawing a line between the plausible early cases in the series and the apparently unacceptable later cases. I argue that no principled reason for drawing this line has been found and that one cannot draw an unprincipled or arbitrary line without begging the question. The paper concludes that, therefore, this defense of the PSR remains unrebutted and that we have a powerful, new reason to embrace the PSR. (shrink)

ABSTRACT According to an important version of the Principle of Sufficient Reason, every fact has a metaphysical explanation, where a metaphysical explanation of some fact tells us what makes it the case that the fact obtains. I argue that, so long as we have not yet discovered that any fact is brute, we ought to be committed to this version of the principle—henceforth ‘the PSR’—because it is indispensable to a species of inquiry in which we ought (...) to engage. I argue, first, that a practical indispensability argument applied to this species of inquiry supports a commitment to the PSR. I then show that we ought to engage in this inquiry. If my argument succeeds, then our attitude at the outset of such inquiry should not be agnosticism about whether any particular fact has a metaphysical explanation. Instead, we ought to be committed to the PSR. (shrink)

This is the second of a series of papers inspired by a paper I wrote around 1989. In this paper, I consider the notion of material contingency and relate it to the traditional, metaphysically loaded Principle of Sufficient Reason.

One conception of the Principle of Sufficient Reason maintains that every fact is metaphysically explained. There are different ways to challenge this version of the PSR; one type of challenge involves pinpointing a specific set of facts that resist metaphysical explanation. Certain identity and distinctness facts seem to constitute such a set. For example, we can imagine a scenario in which we have two qualitatively identical spheres, Castor and Pollux. Castor is distinct from Pollux but it is (...) unclear what could metaphysically explain this distinctness fact. In this paper, I argue that we should not treat identity and distinctness facts as metaphysically fundamental. As such, identity and distinctness facts do not challenge the PSR. We can metaphysically explain them. (shrink)

Metaphysical rationalism, the doctrine which affirms the Principle of Sufficient Reason (the PSR), is out of favor today. The best argument against it is that it appears to lead to necessitarianism, the claim that all truths are necessarily true. Whatever the intuitive appeal of the PSR, the intuitive appeal of the claim that things could have been otherwise is greater. This problem did not go unnoticed by the great metaphysical rationalists Spinoza and Leibniz. Spinoza’s response was to (...) embrace necessitarianism. Leibniz’s response was to argue that, despite appearances, rationalism does not lead to necessitarianism. This paper examines the debate between these two rationalists and concludes that Leibniz has persuasive grounds for his opinion. This has significant implications both for the plausibility of the PSR and for our understanding of modality. (shrink)

This chapter explores an objection to explanatory universalism, the doctrine that the principle of sufficient reason is true or everything has an explanation. This objection is a direct argument to the conclusion that the PSR yields the existence of an omni-explainer, i.e. something that explains everything. The objection crucially relies on the assumption that explanation is dissective in its explanandum place, and its conclusion conflicts with the irreflexivity of explanation. So the chapter considers two responses to the (...) mentioned objection. The first response consisting in restricting the irreflexivity of explanation is criticised in connection with topics in the metaphysics of grounding. The second response consisting in denying that explanation is dissective is vindicated. Finally, the chapter argues that a plausible revised version of the principle that explanation is dissective, the PSR, and the irreflexivity of explanation together yield a striking picture of our universe. (shrink)

Amijee ("Inquiry and Metaphysical Rationalism") argues that as long as we have not yet discovered that any fact is ungrounded, we ought to be committed to a version of the principle of sufficient reason (PSR), according to which every fact is grounded. In this note I present Amijee’s argument, rebut it, and diagnose where it fails. In a nutshell, the issue with Amijee's argument is that in general, rationally searching for something/seeking something/trying to achieve something does not (...) require believing that one is able to reach one's goal. (shrink)

This paper locates a source of contingency for Leibniz in the fact that God can do otherwise, absolutely speaking. This interpretative line has been previously thought to be a dead-end because it appears inconsistent with Leibniz’s own conception of God, as the ens perfectissimum, or the most perfect being (Adams, 1994). This paper points out that the best argument on offer which seeks to demonstrate this inconsistency fails. The paper then argues that the supposition that God does otherwise implies for (...) Leibniz (at least) that God would not be praiseworthy, which is an absurd implication—or a violation of the principle of sufficient reason (PSR)—but that this is not, strictly speaking, an inconsistency—or a violation of the principle of contradiction (POC). While praiseworthiness is a perfection—and is compossible with God’s other perfections—and so God must instantiate it, this paper argues that, given the nature of praiseworthiness for Leibniz, it in fact makes sense to say that praiseworthiness is merely a contingent perfection of God. (shrink)

blandior ratio : C, 34). I will first survey how extensive, albeit usually overlooked, is Leibniz’s concern with these “weaker” forms of reasoning, and how crucial they are for many of his practical and theoretical endeavors. I will then trace back this acute need of Leibniz´s brand of rationalism to the peculiar nature of the Principle of Sufficient Reason (PSR), as opposed to the other basic principle of his philosophy, the Principle of Contradiction (PC). I (...) will present here only the bare bones of the argument, in a sort of extended summary, omitting the textual support as well the references to the relevant secondary literature. (shrink)

It is often assumed that the first stage of many classical arguments for theism depends upon some version of the Principle of Sufficient Reason being true. Unfortunately for classical theists, PSR is a controversial thesis that has come under rather severe criticism in the contemporary literature. In this article, I grant for the sake of argument that every version of PSR is false. Thus, I concede with the critics of PSR, that it is possible that there is, (...) at least, one fact that is ontologically brute. I then proffer an epistemological challenge to ontological bruteness. Specifically, I argue that whenever a knowledge seeker, S, perceives some unexplained fact, F, it is never reasonable for S to believe F is ontologically brute. I conclude that, even if PSR is false, it is more reasonable to believe that the key premise in the first stage of classical arguments for theism is true. (shrink)

Table of Contents: Chapter 1: Wolff and the Refinement of the Mathematical Method / Chapter 2: Wolff’s Emendation of Ontology / Chapter 3: Soul, World, and God: Wolff’s Metaphysics / Chapter 4: Women and the Wolffian Philosophy / Chapter 5: The Abuse of Philosophy: Pietism and the Metaphysics of Freedom / Chapter 6: Reason beyond Proof: Debating the Use and Limits of the PSR / Chapter 7: The Paradoxes of Sensation/ Chapter 8: G. F. Meier on the Fate of (...) the Soul / Chapter 9: Moses Mendelssohn and the Ghost of Spinoza . (shrink)

The goal of this paper is to set out the structure and order of Leibniz’s discussion of the so-called “static shift,” in his correspondence in Clarke. The immediate point of this exercise is to determine precisely how Leibniz puts to use his two famous principles – the Principle of Sufficient Reason (PSR) and the Principleof Identity of Indiscernibles (PII) – in constructing, and defending his relational view of space, while providing a refutation of Absolute Space. In specific, (...) it is to set out an interpretation of this argument contrary to the generally accepted one – here represented by Chernoff – about the use of the PII. (shrink)

The argument for modal collapse is partly responsible for the widespread rejection of the so-called Principle of Sufficient Reason in recent times. This paper discusses the PSR against the background of the recent debate about grounding and develops principled reasons for rejecting the argument from modal collapse.